Printer&#39;s blanket.



P. E. ELLIS.

,PRINTEH'S BLANKET.

APPLICATION FILED SEPT.9,1911.

1 $396,896. Patented May 19, 1914.

*IFFIQE.

FRANK E. ELLIS, OF REVERE, MASSACHUSETTS.

PRINTER/S BLANKET.

Specification of Letters Patent.

Patented May 19, 1914.

Application filed September 9, 1911. Serial No. 648,585.

To all whom it may concern:

Be it known that I, FRANK E. ELLIS, of Revere, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Printers Blankets, of which the following is a specification.

This invention relates to blankets of the kind which are used on the impression cylinders or platens of printing presses to receive the pressure of the printing plates or other forms of types by which printed 1mpressions are made on paper.

The object of the invention is to provide a blanket having sufficient resiliency for the purpose to which it is put, and being at the same time unaffected by oil, free from the liability of oxidizing, to which rubber is subject, and incapable of stretching to any appreciable extent in the usual conditions of use. I

In the accompanying drawings I have illustrated a blanket made in accordance with the principles of my invention, such blanket being one of several possible embodiments, and being chosen for illustration of the principles of the invention because this particular blanket is the. one which at a the present time I consider the most dosirable.

In the drawings, Figure 1 represents a sectional view of the blanket, and Fig. 2 a face View, representing the same as though parts of the several plies or thicknesses had been cut away.

The same reference characters indicate the same parts in all the figures.

In order that the purpose and utility of my invention may be more readily understood I will first make a brief statement of the defects to which the printers blankets heretofore mostgenerally used are subject. Such blankets now in almost universal use are what is known as rubber blankets, being made of two or three plies of textile fabric impregnated with rubber and overlaid by a surfacing coat of rubber having substantial thickness. Such a blanket when used on a printing press cylinder, is wrapped about the impression cylinder of the press with the rubber face outward, and upon it is placed a felt blanket or make-ready sheet which entirely surrounds the rubber blanket and is secured to the cylinder. while being printed upon, is supported by the covering thus provided-on the impression cylinder, Such a covering or impression surface for essary on account of the difficulty of obtaining perfect plates, because the electrotype and stereotype plates used in printing are sometimes warped or sprung out of shape in casting, or bent unevenly in handling. lVithout a resilient blanket, it is impossible to obtain readable and uniform impressions from such plates.

The pressure employed in printin and the rotary motion of the cylinders sub ected to pressure cause the rubber blanket to stretch and become loose, so that after a time the press must be stopped and the slack in the blanket taken up. It is not uncommon for a rubber blanket to stretch as much as an inch on a cylinder 40 inches in circumference, after a few days of use. The slackening of the blanket causes the impression on the paper to be poor and is liable to break the paper, while the stoppages of the press necessary to take up the slack in the blankets of all the impression cylinders results in much delay. Again, the inks used in printing contain oil in their composition, and this oil, after a time, soaks through the outer felt blanket or make-ready sheets, and attacks the rubber blanket, absolutely ruining the latter, so far as its use on the press is concerned. Finally, owing to the high temperature at which press rooms are necessaril y maintained in order to keep the rollers and ink in the best condition for printing, and to overcome the effects of static electricity, the rubber is oxidized, becomes hard, loses its resiliency and cracks. All these causes make the useful life of the ordinary 'priuters blanket very short.

My purpose has been to provide a blanket for the impression cylinders and platens of printing presses which is free from the defects above enumerated of the rubber blanket, and is thereby longer-lived and less expensive in use.

My invention as most broadly stated consists in a printers blanket havingits sur' face which is exposed to the oil of the ink supporting the paper is nec- The paper,

and to the heat of the press room, of such a character as to be unaffected and incapable of injury by the oil and by hot air and moisture and of which the structure is such that it will not stretch appreciably under the conditions to which it is subject in its use. Accordingly the exposed surface of the blanket is provided with a covering of a gum formed of an oxidized vegetable oil, such as linseed, corn, olive or castor oil, or other oil having I the characteristics suitable for my purpose as hereinafter explained.

The body of the blanket is composed of several plies of cloth, preferably of different weaves, whereby the resistance to stretching is augmented, and impregnated and interlined with a composition capable of making the blanket as a whole yielding and resilient.

In the drawings a and I) represent two plies of cloth impregnated with rubber and also rubber-coated on their surfaces. The quantity of rubber is sufficient to form a coating or layer d on the face of the plyb and preferably also a similar layer 0 between the plies a and b. On the surface of the rubber layer d is laid a third ply e of cloth which carries a surface coating f of a gum of the character referred to. The combined fabric is calendered and vulcanized, whereby all the layers are united together and a firm composite fabric is produced, which is suitable for the purposes of a printers blanket;

The portions of the blanket consisting of the rubber coated plies and the ply c with its covering f are made independently of each other and united together after being completed. In making the coated ply or sheet f, the gum is first prepared by oxidizing a vegetable oil, and applying it to the cloth and firmly uniting it thereon by calendering and drying. the purpose of making the coating f, which is oxidizable by boiling in contact with oxygen into the condition of a plastic gum ca:

pable of being spread out into a thin sheet and dried. Accordingly, although linseed oil is the one which I prefer to use, yet I do not limit my invention to a combination including a gum made from the oxidation of this particular oil, nor to one made from any of the other vegetable oils hereinbefore named, namely, corn, olive or castor oil. Likewise I do not limit the invention to rubber as the gum for impregnating and coating the body plies a and 1), since I contemplate using other elastic compositions for this purpose. I prefer also to use differently woven fabrics for the several plies, as indicated in Fig. 2, as thereby the resistance to stretching of the composite fabric is increased. l have illustrated the blanket as including in its construction three plies of textile fabric. I wish it to be understood, however, that I do not limit myself to the Any oil is suitable for use of three and only three plies, for I may use only two plies, or a greater number than three.

I claim,

1. A printers blanket consisting of an elastic body. portion including in its composition a material subject to disintegration by oil, and an outer protective oil-resisting coverin or layer comprising a gum which is inso uble in oil and which is capable of withstanding a vulcanizing heat, said outer protective covering or layer being vulcanized to said body portion and thus permanently associated therewith to form, with said body portion, a unitary fabric.

2. A printers blanket consisting of an elastic body portion including rubber in its composition, and an outer protective oilresisting covering or layer comprising a gum which is insoluble in oil and which is capable of withstanding a vulcanizing heat, said outer protective covering or layer being vulcanized to said body portion and thus permanently associated therewith to form, with said body portion, a unitary fabric.

3. A printers blanket consisting of an elastic body portion including in its compositiona material subject to disintegration by oil, and an outer protective covering or layer comprising an oxidized vegetable oil which is insoluble in oil and which is capable of withstanding a vulcanizing heat, said outer protective covering or layer being vulcanized to said body portion and thus. permanently associated therewith to form, with said body portion, a unitary fabric.

4. A printers blanket consistingv of an elastic body portion composed of one or more plies of textile fabric and rubber, and an outer protective oil-resisting covering or layer comprising an oxidized vegetable oil which is insoluble in oil and which is capable of withstanding a vulcanizing heat,-sa-id outer protective covering or layer being vulcanized to said body portion and thus permanently associated therewith to form, with said body portion, a unitary fabric.

5. A printers blanket comprising an elastic body portion including in its composition vulcanized rubber, and an'outer protective facing composed of fabric previously coated with an oil and ink-proof material, said body portion and said protective facing being permanently united by calendering and vulcanizing.

6. A printers blanket comprising a body portion composed of cloth plies impregnated and coated with rubber and an oil and ink-proof facing vulcanized to said bodyportion.

7. A printers blanket comprising two or mere textile layers having an oil and inkproof facing and a layer of rubber interposed between said textile layers, said several layers and'said facing being calendered and vulcanized together to form a unitary composite blanket.

8. A composite rinters blanket comprising plurality of textile plies coated and impregnated with rubber, a layer of rubber between two of such Flies and a protective facing composed of abric coated with an oxidized vegetable oil and made independently of said rubber-coated and impregnated plies, the latter plies and said facing being 10 permanently united by calendaring and vulcanizing.

In testimony whereof I have aflixed my signature, in presena: of two witnesses.

FRANK E. ELLIS. Witnesses:

A. H. Bnown, P. W. Pmzzm'rn 

